kernel: add function to query CPU clock cycle count

2023-04-22 21:07:34 +01:00
parent a8a6ff123e
commit e7fe5a8f8e
5 changed files with 23 additions and 0 deletions
--- a/arch/x86_64/cpu_ctrl.S
+++ b/arch/x86_64/cpu_ctrl.S
@@ -38,3 +38,13 @@ wrmsr:
 	wrmsr

 	ret
+
+
+	.global get_cycles
+	.type get_cycles, @function
+
+get_cycles:
+	rdtsc
+	shl $32, %rdx
+	orq %rdx, %rax
+	ret